Production method of the female screw parts, female screw parts, and threaded connection

摘要

I will provide a threaded connection portion including a female screw parts manufacturing method suitable female screw parts, and the female screw parts, suitable, and to carry out the screwing or automatic / [challenge] to absorb a large force. Were prepared by pressing the blank 13 having an inner diameter section 5 of the inner diameter D _f larger than the inner diameter portion 3 of the inner diameter D _k, a manufacturing method of the internal thread part of the present invention comprises the mandrel into the opening 14 The insert 17, and the same inner diameter of the bore 3 and 5 both by performing press working on a blank 13, remove the mandrel 17 from the opening 14, and processes the internal thread 4 and 6 in the bore 3 and 5 both positioned to each other the internal thread portion 20, 21 of both to form a female screw portion 20, 21 Te, braking torque to occur during the screwing by performing adjustment relative to the female screw portion 20 and 21, the internal thread portion 20, 21 I form the axial dimension is, and to be identical to each other, the dimensions of the contact surface of the opposite ends thereof to be identical to each other. [Selection] Figure Figure 1